In the past electrical cables, whether for power, telephone, television or communication have typically been mounted on poles stretched above ground. In recent years a trend has developed in which more and more electrical cables are run underground, particularly in residential areas. It is a common practice to install facilities for connecting or disconnecting underground cables and for this purpose accesses are required. The typical access to an underground cable is called a "pedestal" and is an open top and open bottom structure, usually circular in horizontal cross-sections. It is buried in the ground with the open top extending above the ground. The cables are brought into the pedestal through the open bottom and extend upwardly through the open top. A pedestal cover is then used to close the pedestal to prevent access to the underground cables, and the connections made in the pedestal, from all but authorized personnel. Unauthorized access to underground cables can, in the case of power cables, be extremely hazardous and in the case of telephone, television or communication cables can provide the opportunity for mischiefwherein services can be disrupted. In addition, it is important to prevent entry of rain and snow out of the underground pedestal.
For all these reasons, a cover plays an important part in the effective use of a pedestal to provide access to underground wiring. It is important that provision be made whereby covers can be locked onto a pedestal. An improved system for providing a safety lock for a pedestal cover is the subject of this disclosure.
2. Prior Art As an example of a type of cover employed on a pedestal that receives underground cables reference may be had to U.S. Pat. No. 3,812,279 entitled "Cable Television Housing With Lockable Joined Cover and Base". For additional background information relating to devices that are lockable on closures, see the following United States Patents:
__________________________________________________________________________ U.S. PAT. NO. INVENTOR TITLE __________________________________________________________________________ 3279838 Hamilton Locking Securement For Sheet Metal Housing Cover 3286133 Sturdivan Meter Pedestal 3341718 Acker Combined Street Light and Residential Power Construction 3450945 Wurdack Circuit Switching Aid Protecting Arrangement 3466379 Lohman Underground Utility Cable or Conduit Terminal 3530781 Kesinger Transformer Housing And Vented Cover Assembly 3652779 Grinols Underground Cable Pedestal 3709401 Walstrom Tamper Resistant Fastening Apparatus 3755614 Jakacki Sealed Underground Wiring Test Station 3812279 Voegeli Cable Television Housing With Lockably Joined Cover and Base 3938285 Gilbu Manhole And Method of Manufacture 3974933 Toth et al Explosion Proof and Watertight Enclosure With Inspectable Means For Verifying Validity Of Reclosure 4059199 Quaney Utility Box Fastener 4089139 Moffa et al Segmented Cylindrical Reinforced Plastic Manhole Structure 4097683 Summers Terminal Housing For Buried Electrical Cables and Method Of Expanding Same 4190734 Dressler, Jr. Cable Pedestal Rodent Guard System, Method of Constructing Same, and Kit and Composition 4213111 Lux, Jr. Ground Level Transformer Unit 4267399 Lux, Jr. Transformer Pad With Cable Protective Sleeve 4534586 Smith Automatic Locking Device 4579248 Gorges Access Panel Assembly For Aircraft Fuel Tank 4626616 Masters Anti-Tapping Device To Prevent Unauthorized Connections To Electrical Utility Service Cables 4631353 Marks Terminal Pedestal For Buried Cable Installation 4632269 Rose Waterproof Electrical Enclosures 4723866 McCauley Manhole Cover Locking Bolt Construction 4772154 Caroulle Sealing Gasket For A Broadway Manhole 5111000 Maraldo Enclosure For Semi-Buried Electrical Distribution Apparatus 5117067 Jaycox Environmentally Sealed Pedestal 5134541 Frouin Distribution Station For Water And/Or Gas And/Or Fuel And/Or Electricity And/Or Any Other Fluid 5235133 Roth et al Housing 15312202 Newton Access Cover Assembly RE 31,134 Lux, Jr. Ground Level Transformer Unit Italy 704591 Bassani Metodo e dispositivo per ricavare cavite per l'incasso di installazioni elettriche in plafoni in getto di cemento __________________________________________________________________________